This section provides background information related to the present disclosure which is not necessarily prior art.
Batteries, whether disposable or rechargeable, provide the energy source for a wide range of portable devices. There is growing interest in so-called smart batteries, which communicate over a wired communication interface, known as the System Management Bus or SMBus to perform power management operations. In a typical smart battery system, an integrated circuit in the battery pack monitors the battery and reports information to external devices via the SMBus. The reported information might include battery type, model number, manufacturer, discharge rate, predicted remaining capacity, temperature and voltage (temperature and voltage being relevant to fast-charging).
In order to use this SMBus information, the device into which the battery is installed must be designed to make specific use of the information. For example, a laptop computer or mobile phone might be designed to report the battery charge remaining as a graphical icon on the device display screen. Similarly, battery charges incorporated into these devices make use of the temperature and voltage information in order to provide safe fast-charging.
While devices equipped with SMBus-enabled smart batteries are certainly advantageous, the conventional smart battery technology leaves thousands of products without any practical way to benefit from this technology. The simple flashlight, for example, is ill-equipped to take advantage of smart battery technology, for the simple on-off function of the flashlight has no way to utilize information coming from the SMBus. Moreover, even more sophisticated products, such as digital cameras, which might potentially use SMBus information, may still lack important charge level awareness information or lack the ability to communicate that information in a manner that is intuitive to the user.
When they think about it at all, most users make assumptions about the battery charge levels within their devices. The mindfully prepared user removes batteries and tests them frequently, or uses fresh batteries before embarking on an adventure where fresh batteries and charging stations will be unavailable. The careless or uninformed user simply proceeds on the adventure without giving battery charge level a second thought—until the batteries fail, perhaps far from civilization.